The immediate drainage of water from exposed surfaces on a building such as roofs, balconies, terraces, etc. is important to protect the structure of the building from corrosion and moisture. For drainage, gravity or vacuum systems can be utilized. Siphonic systems (Bernoulli's Theorem) are used for draining on large surfaces and especially non-accessible areas where dirt is limited. In the event of blockages, EN 1253 also requires the use of gravity type safety drains in case of overflow.

The most common and reliable method of drainage is the use of gravity systems, especially in regions such as Greece with long periods of drought and extreme rainfall that create sediment blockages in the systems. An important factor in the selection of systems is 1) the interaction and cohesion of the drain with the roofing felt or wet insulation, 2) the correct choice of grating both to avoid blockages and for the correct choice of load capacity category for accessible areas.

As part of its product range, enflow designs and offers drainage systems for various types of roofs.

The complete range of drains developed by enflow includes vertical and two way roof outlets made entirely of aluminum for maximum protection against corrosion. They are suitable for use with most types of waterproofing membrane. The outlet of the drain can be connected to threaded or unthreaded cast iron pipes, HDPE pipes and PVC pipes by means of a suitable plastic connector.


Enflow aluminum two way outlet can be installed to provide vertical or horizontal drainage. The outlet for drain has been constructed in all the usual sizes used in projects in Greece and the range includes: 2’’, 3’’, 4’’ 5’’ and 6’’.
All drains are threaded, ensuring complete waterproofing.

Product code Outlet size Nominal size (mm)
N-TWO2 2” 50
N-TWO3 3” 75
N-TWO4 4” 100
N-TWO5 5” 125
N-TWO6 6” 150


Aluminum vertical outlets are suitable for all types of flat roof applications. They are available with an inverted basket or flat grate. Inverted basket grates allow rainwater to flow freely, preventing the entry of debris, while flat grates are used in areas where pedestrian traffic is expected. Both of the above types of grating can be removed without affecting the main body of the drain, the clamping ring or the sealing membrane.

Product code Outlet size Nominal size (mm)
N-VTO2 2” 50
N-VTO3 3” 75
N-VTO4 4” 100
In addition, in collaboration with foreign companies, enflow can supply roof drains made of plastic or cast iron to meet the needs of any project.